Role of steps in N2 activation on Ru(0001)

被引：697

作者：

Dahl, S ^{[1
]}

Logadottir, A

Egeberg, RC

Larsen, JH

Chorkendorff, I

Törnqvist, E

Norskov, JK

机构：

[1] Tech Univ Denmark, Ctr Atom Scale Mat Phys, Dept Phys, DK-2800 Lyngby, Denmark

[2] Tech Univ Denmark, Interdisciplinary Res Ctr Catalysis, DK-2800 Lyngby, Denmark

[3] Haldor Topsoe Res Labs, DK-2800 Lyngby, Denmark

来源：

PHYSICAL REVIEW LETTERS | 1999年 / 83卷 / 09期

关键词：

D O I：

10.1103/PhysRevLett.83.1814

中图分类号：

O4 [物理学];

学科分类号：

0702 ;

摘要：

Using adsorption experiments and density functional calculations we show that N-2 dissociation on the Ru(0001) surface is totally dominated by steps. The measured adsorption rate at the steps is at least 9 orders of magnitude higher than on the terraces at 500 K, and the corresponding calculated difference in activation energy is 1.5 eV. The low barrier at the step is shown to be due to a combination of electronic and geometrical effects. The consequences for Ru as a catalyst for ammonia synthesis are discussed.

引用

页码：1814 / 1817

页数：4

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